Yellowmargined flea beetle management on crucifer crops

This presentation was delivered at the eOrganic webinar where it is archived with audio. This is the basic IPM presentation given to national audience on December 2, 2014. Presentation focuses on the management of yellowmargined flea beetles - a major insect pest of crucifers on organic/small farms.

1. IPM in Crucifers: Focus on Yellowmargined Leaf Beetle Presenters : Rammohan Balusu 1 , Ron Cave 2 , and Ayanava Majumdar 3 1 Auburn University 2 University of Florida 3 Alabama Cooperative Extension (USDA – NIFA Award # 2011-51300-30634) Co-authors : Henry Fadamiro 1 , Oscar Liburd 2 , and Elena Rhodes 2 December 2, 2014

2. Presentation Layout Introduction Research findings from Alabama Research findings from Florida Combined IPM recommendation Extension IPM resources

3. Topic Relevance Organic crucifer production is a challenge in southern U.S. Low number of certified organic acreage (USDA, 2008) Major problems with crucifer production: Pests destroy or contaminate produce at critical point of production resulting in yield or quality loss. Insect pests like the Yellowmargined Leaf Beetle (YMLB) are year-round problem in the hot and humid South. Lack of effective organic integrated pest management (IPM) tactics.

4. OAREI Objectives: YMLB Focus Research objectives (based on NOP standards): Level 1: System-based practices: Trap crops and biological control agents Level 2: Mechanical and Physical practices Level 3: OMRI approved bio-insecticides Producer training (ongoing) Developing new IPM educational resources (ongoing)

5. Key pest of organic crucifers in the South Yellowmargined leaf beetle or YMLB, Microtheca ochloroma ( Coleoptera : Chrysomelidae ) Native to South America First reported in Mobile, AL in 1947 Distribution Yellowmargined leaf beetle

6. Multiple generations ~30 days to complete life cycle at 22°C YMLB Biology Adults 16 – 180 days Eggs 8 days Pupa 9 days Larva 10 days

7. Larvae on turnips Adults on napa cabbage YMLB Damage

8. Fall Soil Spring Behavior & Ecology

9. “Organically-managed” crucifer field in south A labama damaged by YMLB Turnip Napa cabbage Complete crop loss

10. Level 1: System-based practices Trap cropping for YMLB Perimeter trap cropping - planting a more attractive crop on field borders to protect the main cash crop. Intercepts and concentrates the pest population in the border. YMLB is a good candidate for trap crop management Trap crop Cash crop Cash crop only Perimeter trap cropping Conventional planting Show host preference Migrate into the field Exhibit strong edge effect Limited mobility

11. Could we use turnip as trap crop to manage YMLB? Trap crop: Turnip Cash crops: Cabbage/ Mustard/ Napa cabbage Data collection Larvae Adult Damage rating at harvest Methods Damage rating scale 1 = very light defoliation (< 10%) 2 = light defoliation (10-30%) 3 = moderate defoliation (30-50%) 4 = heavy defoliation (50-70%) 5 = very heavy defoliation (70-90%) 6 = complete defoliation (> 90%)

12. Field layout Turnip trap crop was planted two weeks ahead of cabbage cash crop 40 ft 2.5 ft 3.5 ft

13. Is turnip an effective trap crop for YMLB ? Cash crop only Cash crop (cabbage) bordered by trap crop Trap crop (turnip)

14. Perimeter trap cropping with turnip attracted beetles away from cabbage cash crop. Results A B

15. Summary Turnip is highly attractive trap crop for YMLB in organic cabbage production system Perimeter planting of turnip in the border of cabbage field limit YMLB infestation on the border. Trap crop management is necessary – single application of insecticide on turnip trap crop effectively reduced YMLB damage on cabbage cash crop.

16. Biopesticides and botanical insecticides were tested as last resort therapeutic tools for control of YMLB PyGanic ® Entrust ® NOFLY ™ Grandevo ™ Entrust ® alternated with NOFLY™ Entrust ® alternated with PyGanic ® Control Level 3: Biorational insecticides: Biopesticides for YMLB PyGanic ® Enstrust ® NOFLY™ Grandevo ™

17. Field layout Data collection: Larvae Adult Damage rating at harvest 3.5 ft 35 ft 2 .5 ft Damage rating scale 1 = very light defoliation (< 10%) 2 = light defoliation (10-30%) 3 = moderate defoliation (30-50%) 4 = heavy defoliation (50-70%) 5 = very heavy defoliation (70-90%) 6 = complete defoliation (> 90%)

18. Results Enstrust ® , PyGanic ® > Grandevo ™ >NOFLY™

19. Results

20. Entrust ® Vs Control Entrust ® Control

21. Summary Entrust ® and PyGanic ® consistently performed well in suppressing YMLB adults, larvae and crop damage Grandevo ™ was effective against larvae Entrust® can be applied in rotation with NOFLY™ and PyGanic ®

22. Crucifer IPM Recommendations and Educational Resources

23. IPM Recommendations: Scouting for YMLB Look for adult beetles – one adult per plant is a warning! Host preference: Turnip > napa cabbage > mustard > cabbage > collard Look for early defoliation on turnips This is too late!

24. IPM Recommendations: Prevent buildup/outbreak! Field sanitation is important Larvae are more susceptible to freezing temps. Protect or release natural enemies Don’t leave them uncontrolled!

25. IPM Recommendations: Trap Cropping Trap cropping (TC) strongly recommended: Perimeter TC with turnips: Plant TC two-weeks before main crop Control YMLB on trap crop Weekly scouting Treat when numbers exceed 1 adult per plant Biopesticides listed on next slide

26. Natural enemies (generalist predators) Protect or conserve natural enemies that have been shown to be effective predators of YMLB Reduce or eliminate pesticide sprays on main crop by using trap crops Spined soldier bugs Adults can feed on 6 YMLB larvae/d Green lacewings Each lacewing larva can feed on 500 eggs or 42 YMLB larvae/d

27. IPM Recommendations: Biopesticides Effective biopesticides : Spinosad (Entrust ®): Adults, larvae Pyrethrin ( PyGanic ®): Larvae Chromobacterium subtsugae ( Grandevo ®): Larvae Isaria fumosorosea ( NoFly ®): Larvae PyGanic , Grandevo , and Isaria good for rotation On trap crop, one or two appl. of s pinosad may be enough… Spray main crop as needed - do NOT overspray to protect natural enemies!

28. Intensive Producer Training and Rapid R esponse IPM Campaign Farmer-to-farmer Resolving urgent pest issues 50% or more crop saved by timely intervention

29. Alabama IPM Communicator – a major resource for producers Team publication since 2010 1450 subscribers Available as PDF (numbered Ext. bulletin) and… Web-based for mobile devices!

30. New Extension Resources in Alabama New Producer Handbook and Alternative IPM Slide charts for use by small producers.

31. www.aces.edu/go/87 For Ext. publications, please email [email protected]

32. Vegetable IPM on Facebook! Advantages: Rapid pest alerts, interactive, insect ID photos and videos, success stories, IPM contest

33. Acknowledgments Research funding provided by USDA-NIFA OAREI Grower participants in AL, FL and GA Field research staff at university farms Alabama Vegetable IPM Program Assistant: Ann Chambliss